vmoranv jshookmcp 0.3.1 server-side request forgery

Summaryinfo

A vulnerability was found in vmoranv jshookmcp 0.3.1 and classified as problematic. The affected element is an unknown function. Such manipulation leads to server-side request forgery. This vulnerability is uniquely identified as CVE-2026-49856. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in vmoranv jshookmcp 0.3.1. It has been rated as problematic. Affected by this issue is an unknown code. The manipulation with an unknown input leads to a server-side request forgery vulnerability. Using CWE to declare the problem leads to CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. Impacted is confidentiality. CVE summarizes:

@jshookmcp/jshook is an MCP server that gives AI agents tools for JavaScript analysis and security research. In version 0.3.1, he network domain has a central SSRF authorization policy that blocks private, loopback, link-local, and reserved targets unless an explicit authorization object allows private network access. The policy is enforced by raw HTTP/TCP/TLS RTT tools, but the ICMP probe and traceroute tools resolve the target and invoke the native ICMP/traceroute sink directly. An MCP client with access to an active network domain can therefore ask the jshookmcp server to probe internal addresses even when local SSRF access is disabled for the other raw network tools. This exposes an internal reachability and route mapping primitive from the server network position. Version 0.3.2 fixes the issue.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-49856 since 06/02/2026. The exploitation is known to be easy. The attack may be launched remotely. The technical details are unknown and an exploit is not available.

Upgrading to version 0.3.2 eliminates this vulnerability.

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Productinfo

Vendor

• vmoranv

Name

• jshookmcp

Version

• 0.3.1

Website

• Product: https://github.com/vmoranv/jshookmcp/

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